"It's a true film. I am very much connected to the subject and the idea of the script. I have not yet started working on the film yet. But we are happy that we have got a nod from Kishore Kumar's family to make this film," Basu told.
"Before this film, Ranbir will be doing two more films with other directors, and then this film will go on floors. So I believe Kishore Kumar's biopic should start by winter 2013," he added.
Basu says the legendary singer's son Amit Kumar is helping them with the research regarding the film, which is expected to have lilting melodies and a powerful soundtrack, given Kishore Kumar's repertoire.
"We have to work very hard on the music of this film. But it's too early right now because presently it's only me, Ranbir and UTV, who are part of this project. Kishore Kumar's son Amit Kumar is helping us a lot with this film. He is helping us with the research and keeps us updated about everything," he added.